After glass bottles and similar glass containers have been made and annealed in the lehr, it is necessary to inspect, sort and organize them. Principal matters looked for in the inspection are whether the bottles have the desired symmetry, are free of defects and have the proper size and shape of mouth and neck for receiving a closure. In the sorting operation, containers which have failed to pass one of the inspections are culled from the bottles which have been found acceptable. Often bottles are made by another entity than the one which will fill them, and so in the organizing operation, the bottles are arranged in a common orientation and put in boxes for shipment and storage. Even where bottle manufacture and filling is run in tandem by the same entity or by two entities with colocated facilities, intermediate boxing or palleting of the bottles is usually necessary due to production lags between when the bottles are made and when the filling entity is ready for them. Manufactures of glass bottle manufacturing equipment include, Owens-Illinois, Emhart, Powers Manufacturing Co., Ball Corporation and Brockway Glass Co., among others.
Electronic Inspection Machines, Inc., 1001 South Delsea Drive, Millville N.J. 08332 manufactures a device for inspectiong bottles having a round transverse cross-section. The device, a Model 317 Check Master is a straight-through feed, optical/electronic inspection machine utilizing phototransistors and normally performing four checks per bottle: finish, barrel, neck and bottom. Inspection speed, depending on bottle size, ranges up to 130 per minute (260 per minute in tandem). Inspection head indexing is by worm feed and the inspection head is adjustable to inspect containers of any height, and of 1.75 to 4.0 inch diameter. The Model 317 does not process non-round e.g., square cross-section bottles, because rotation of the bottles during inspection is, in this model, achieved by contacting each bottle sidewall with a rotating friction wheel while the bottle rests on a support.
As one may well imagine, as time progresses, developments in glass bottle manufacture do result in increases in output rate. For instance, the output of the lehr of one manufacturing line may be 300 bottles per minute, or more. The manufacturing speed increase has placed stress on the conduct of cold end inspection. The flow of the work and the reliability of the inspection have become problems.